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Chronic simian immunodeficiency virus infection is associated with contrasting phenotypes of dysfunctional Bcl6⁺ germinal center B cells or Bcl6^- Bcl2⁺ non-germinal center B cells.

ABSTRACT: Human immunodeficiency virus (HIV) infection is characterized by dysfunctional B cell responses. Here we show that chronic simian immunodeficiency virus (SIV) infection is characterized by an expansion of either lymph node germinal center (GC) B cells that co-express Bcl6, Ki-67 and IL-21R and correlate with expanded T follicular helper (Tfh) cells or B cells that lack Bcl6, Ki-67 and IL-21R but express high levels of anti-apoptotic Bcl2 that negatively correlate with Tfh cells. The lack of Tfh cells likely contributes to persistence of dysfunctional non-proliferating B cells during chronic infection. These findings have implications for protective immunity in HIV-infected individuals who harbour low frequencies of Tfh cells.

SUBMITTER: Onabajo OO

PROVIDER: S-EPMC6201227 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Chronic simian immunodeficiency virus infection is associated with contrasting phenotypes of dysfunctional Bcl6+ germinal center B cells or Bcl6- Bcl2+ non-germinal center B cells.

Onabajo Olusegun O OO Lewis Mark G MG Mattapallil Joseph J JJ

Journal of cellular and molecular medicine 20180906 11

Human immunodeficiency virus (HIV) infection is characterized by dysfunctional B cell responses. Here we show that chronic simian immunodeficiency virus (SIV) infection is characterized by an expansion of either lymph node germinal center (GC) B cells that co-express Bcl6, Ki-67 and IL-21R and correlate with expanded T follicular helper (Tfh) cells or B cells that lack Bcl6, Ki-67 and IL-21R but express high levels of anti-apoptotic Bcl2 that negatively correlate with Tfh cells. The lack of Tfh ...[more]

PMID: 30191661

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